George e



(No Model.)

G. E. S'UHOPER.

DOOR KNOB.

Patented Mar. 3, 1896.

{Z71 al 2% Inventor Attorney.

. NITED STATES PATENT OFFICE.

GEORGE E. SOHOFER, OF READING, PENNSYLVANIA, ASSIGNOR TO THE READING HARDWARE COMPANY, OF SAME PLACE.

DOOR-KNOB.

SPECIFICATION forming part of Letters Patent No. 555,906, dated March 3, 1896.

Application filed October 19, 1895. Serial No. 566,229. (No model.)

To all whom it may concern:

Be it known that I, GEORGE E. SOHOFER, a citizen of the United States, residing at Reading, county of Berks, State of Pennsylvania, have invented a certain Improvement in Door-Knobs, of which the following is a specification.

My invention relates to that class of doorknobs in which a sheet-metal shell is united to a shank of cast-iron or other unmalleable material; and my object is to provide an improved construction in which these two pieces are firmly and economically united without any additional material.

The invention is fully described in connection with the drawings, and is specifically pointed out in the claim.

Figure 1 shows in cross-section the sheetmetal shell and the cast-metal shank before uniting them. Figs. 2 and 3 are plan views of the shell and shank, respectively. Fig. 4 shows the sheet-metal shell forced part way upon the boss. Fig. 5 shows it forced down against its seat on the shank-collar. Fig. 6 shows it firmly united to the shank.

A represents a cast-iron knob-shank,which is formed with a collar a and a boss I) to engage the sheet-metal part D of the knob. This boss is of an angular or irregular form corresponding with the central opening 6 in the shell, so as to prevent any possibility of one part turning upon the other. The extremity of the boss b tapers outward, as indicated at a, while near its junction with the collar a it is undercut, as shown at c.

The central opening e in the sheet-metal shell D is inclosed by an upwardly-turned edge of metal f, which rests upon the tapering portion 0 of the shank-boss when the shell is placed loosely upon the latter, as shown in Fig. 1. As the shell is forced down upon the shank-boss the edge metal f springs sufficiently to enlarge the opening 6, so that it may pass over the largest part of the boss, as shown in Fig. 4, and finally drop into the under-cut or recess 0, Fig. 5, as the base of the shell is seated against the collar a, into which under-cut it is finally pressed, as shown in Fig. 6, thus uniting the two parts in a most satisfactory and rigid manner.

I am aware that sheet-metal shells have been heretofore secured to cast-metal knobshanks, and therefore desire to confine my invention to the improved means of uniting these parts substantially as described and claimed, the chief advantage of which is extreme simplicity and economy combined with rigidity of structure.

What I claim is- The combination with the knob-shank having a collar a and an angular boss 11 with tapering end 0 and under-cut c, of the sheetmetal knob-shell D having a central opening to admit the angular boss and an upturned edge f around said opening, the parts being united by forcing the shell over the tapered end of the boss and said upturned edge metal tightly into the under-cut, substantially as described.

In testimony whereof I affiX my signature in presence of two witnesses.

GEORGE E. SCI-IOFER. Witnesses:

GEO. E. TYSON, CHARLES E. STOUT. 

